It's yet another cheapo LED strip from AliExpress! Every strip I buy seems to get cheaper and cheaper. I find it strange that every manufacturer seems to implement their own controller and so each set of lights has a different protocol. But here we are.
This time I paid £2.52 including tax and delivery for a 5M strip with an IR remote control. The remote didn't include a battery. The app is called HiLighting. It forces you to enable precise location on Android before it will even detect your lights and allow you to control them! There is some interesting looking functionality which allows you to choose your own colour scheme for the effects. I don't think I will spent too much time with that since it's not supported in Home Assistant, but we'll see.
Something to be aware of is that the picture on the AliExpress page for the product doesn't necessarily represent the app or the controller that the lights will use.
AliExpress link: https://s.click.aliexpress.com/e/_DD74ZBn
My lights report their name as: L7161 and have a MAC address of 23:01:02:aa:10:84.
Planned implementation complete.
Working:
- On / Off
- Set RGB colour
- Brightness
- Limited effects with a fixed speed
You need to have the bluetooth component configured and working in Home Assistant in order to use this integration.
Add this repo to HACS as a custom repo. Click through:
- HACS -> Integrations -> Top right menu -> Custom Repositories
- Paste the Github URL to this repo in to the Repository box
- Choose category
Integration - Click Add
- Restart Home Assistant
- HiLighting LED devices should start to appear in your Integrations page
As with the ELK-BLEDOB project I will be using an nRF52840 BLE Sniffer rather than trying to get snoop logs off Android. So let's breakout Wireshark and go fishing...
Tips if you're using Wireshark and a nRF52840 with the Nordic toolkit:
- Filter
btle.length != 0will hide empty PDU packets - Filter
btatt.handle == 0x0014will show writes to the serial port
It looks like this set of lights offers a serial port over Bluetooth LE and then you send commands to it that way. Had a chat on the Home Assistant Discord and the feeling is that if it's GATT then it should just work, so I'm going to try and implement a simple on/off integration before digging in to all the complex stuff. ... and ... it does indeed just work.
If you have a BLE UART connection you just write these bytes to the serial port. Using an app like LightBlue you can connect to the controller, connect to 6e400002-b5a3-f393-e0a9-e50e24dcca9e and write these hex bytes.
55 01 02 00Off55 01 02 01On
|------|------------------------ header
| | ||--------------------- red
| | || ||------------------ green
| | || || ||--------------- blue
55 07 01 ff 00 00
55 07 01 00 ff 00
55 07 01 00 00 ff
Brightness is odd.
|------|------------------------ header
| | |---|------------------ brightness
55 03 01 09 03
55 03 01 6c 02
55 03 01 6f 05
Minimum brightness is 0x6c 0x02 (27650) Maximum brightness is 0xff 0x0f (65295)
It seems that the two brightness bytes do not represent a single value. Byte 4, the last byte, is a scale which stops at 0x0F. Byte 3 is the smaller increments which seems to be an 8 bit number. I don't think it's really necessary to have that level of granularity on these type of LEDs, so I've only implemented the 15 levels of brightness from byte 4. This seems fine.
The standard effects numbered from 0 to 9. You don't seem to be able to specify a brightness for them.
|---|--------------------------- header
| | ||------------------------ select effect
| | || ||--------------------- effect number
55 04 01 00
55 04 01 01
55 04 01 06
55 04 01 07
|---|--------------------------- header
| | ||------------------------ select effect speed (0-255)
| | || ||--------------------- speed
55 04 04 31
55 04 04 59
55 04 04 96
55 04 04 bf
55 04 04 ff
We could build a set of custom effects and hard code them as part of the integration. But I'm not planning on doing that any time soon. The format seems easy enough to understand.
|------| --------------------------------------------------------------------- custom effects header
| | ||------------------------------------------------------------------- speed probably 0-255
| | || ||---------------------------------------------------------------- effect type (merge, flash etc) probably 1 -> 5
| | || || ||------------------------------------------------------------- brightness probably 0-255
| | || || || |---------------| ------------------------------------------ likely all colour data. 2 bytes per colour? 565?
55 05 01 00 03 00 fa f8 55 f9 b1 ff - RGB merge, slow, dim
55 05 01 00 03 ff fa f8 55 f9 b1 ff - RGB merge, slow, bright
55 05 01 7f 03 00 fa f8 55 f9 b1 ff - rgb merge, fast, dim
55 05 01 7f 03 ff fa f8 55 f9 b1 ff - rgb merge, fast, bright
55 05 01 7f 04 ff fa f8 55 f9 b1 ff - rgb flash, fast, bright
55 05 01 7f 05 ff fa f8 55 f9 b1 ff - rgb, jump, fast, bright
55 05 01 7f 05 ff fa f8 41 f9 fc fd 4d e4 - rgrg, jump, fast, bright